Long term evolution (LTE) and other radio communications technologies can require significant infrastructure and configuration. Generally, network operators test various aspects of their network equipment to ensure reliable and efficient operation. Network operators typically simulate various conditions before equipment is deployed in a live network to decrease avoidable delays and/or other problems.
Various technical specifications, such as the 3rd Generation Partnership Project (3GPP) Technical Specifications 36.211, 36.212, 36.213, and 36.214, hereinafter respectively referred to as “TS 36.211”, “TS 36.212”, “TS 36.213”, and “TS 36.214”, define aspects of LTE communications. Generally, data from the network to a user device is referred to as downlink data and data from the user device to the network is referred to as uplink data. For example, user equipment (UE), such as a cellular mobile phone or a tablet computer, may communicate with an enhanced or evolved Node B (eNode B) via the cellular radio transmission link. Data that is sent from the eNode B to the UE is downlink data, and data that is sent from the UE to the eNode B is uplink data.
Uplink and downlink LTE data is usually transmitted using one or more multiplexing and/or modulation schemes. For example, in some LTE networks, downlink data is transmitted using an orthogonal frequency-division multiplexing (OFDM) and uplink data is transmitted using single carrier frequency-division multiple access (SC-FDMA). Such schemes may allow multiple streams of data to be sent simultaneously (e.g., at different frequencies). While such schemes may allow data to be communicated at high-speed, significant processing is required to encode and decode the data. For example, an eNode B may perform channel coding, multiplexing, and interleaving of data and control streams, which are then sent to the UE over the air (RF) interface. After pre-processing the received signal from the eNode B, the UE may perform channel delineation for downlink physical channels and/or other baseband processing. After separating LTE data from various physical layer channels, the LTE data may be further processed.
Since LTE communications are generally complex and processing is time-sensitive, it is important for baseband processing to be performed quickly and efficiently. Further complexity is added, when radio channel propagation conditions are simulated. For example, conventional methods of testing radio channel conditions involve manipulating or modifying the radio frequency signal or the baseband equivalent (e.g., the signal or data sent from the eNode B). While manipulating the baseband for testing channel conditions associated with a single UE is possible, manipulating the baseband for each of a plurality of simulated UEs present significant challenges, including being very resource-intensive. Further, performing baseband manipulation in addition to other baseband processing for each of a plurality of simulated UEs within an acceptable time frame can be very challenging.
Accordingly, in light of these difficulties, a need exists for improved methods, systems, and computer readable media for simulating radio channel conditions.